There's a text Brits can send which could save millions of people money on their phone bill, says money saving expert Martin Lewis.
It's estimated around 14 million people in the UK are out of contract with their network provider, meaning they are basically paying over the odds for an outdated deal.
Providers are expected to raise prices by eight percent at the start of April too, even if mid-contract.
But Martin says there's one text that can be sent to see if mobile phone users in the UK are out of contract and can therefore either get a better deal on an upgrade or SIM card with the same or different providers.
@martinlewismse A simple text that could slash your mobile bill Feel free to share
In a TikTok video, Martin said: "Why not text 'info' to 85075 - it's free and it will tell you whether you're one of 14 million people in the UK who are currently out of contract and therefore free to switch and can likely save a shed load.
"I should note, there are a few times it doesn't work, such as if you've got a contract where there's multiple phones in a household in which case, if you've been with the same provider for more than two years, you're likely out of contract now.
"The reason I'm doing this right now, and had the thought while I'm having a walk, is because at the start of April, prices on most phone networks are going to rise eight percent even if you're mid-contract, which is absolutely outrageous.
"It's something I've written to the Chancellor about and lobbied about but we've not had any change yet.
"It's a really good opportunity to see if you can save."
Martin also has tips on the best deals to look for if switching.
"The best deals aren't direct - they're going through comparison sites where they (providers) put marketing budget into get you better prices," he said.
"Remember, there are only four mobile networks in the UK - every other one is piggybacking off one of those four, so you want to do a comparison that says 'what's the cheapest deal on the signal that I currently have?'"
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